I guess that both "ayúdame" and "¿me ayuda?" when we are talking to other person can mean the same thing, but the feeling behind it is kinda different.

If someone say to me "ayúdame" (wich means"help me" in english) is kinda a command, so we usually use this expression to people we are close like friends and family.

"me ayuda" can be applied in two situations:*As a question "¿me ayuda?" it can be a more polite way to ask for help, because it translates like "would you help me?"* In sentences like "Tom me ayuda a cocinar" = Tom helps me to cook, it means that someone (or something) is helping me.